app.directive('closePopupBackDrop', ['$ionicGesture', function($ionicGesture) {
    return {
        scope: false, //共享父scope
        restrict: 'A',
        replace: false,
        link: function(scope, element, attrs, controller) {
            //要在html上添加点击事件, 试了很久- -!
            var $htmlEl = angular.element(document.querySelector('html'));
            $ionicGesture.on("touch", function(event) {
                if (event.target.nodeName === "HTML" && scope.myPopup.isPopup) {
                    scope.optionsPopup.close();
                    scope.myPopup.isPopup = false;
                }
            }, $htmlEl);
        }
    };
}])